Dynamic interactive identity authentication method and system

A dynamic interactive identity authentication system comprises a server-side and client-side(s) which is in communication connection with the server-side, characterized in that the system comprises:

• a storage unit for storing a user password comprising a number of characters chosen from a parent character set;
• a display character set generating unit for generating L display character sets each containing at least two characters after receiving a request for identity authentication, said L display character sets comprising M valid character set(s) and L-M interference character set(s), each of the said valid character set having one valid password character and each of the said interference character set having none of the valid password characters, wherein both L and M are integers greater than 0, L>M;
• a display unit for displaying said L display character sets;
• an inputting unit for inputting a number of characters each chosen from each one of the said L display character sets to form a dynamic inputting code;
• and
• a password authentication unit for receiving the dynamic inputting code from the inputting unit and comparing the dynamic inputting code with the user password,
• wherein said display unit and said inputting unit set up in the client-side(s), said storage unit, said display character set generating unit and said password authentication unit set up in the client-side(s) or server-side.